In a gas turbine engine, air is pressurized in a compressor then mixed with fuel and burned in a combustor to generate hot combustion gases. These pressurized hot combustion gases are expanded within a turbine section that may include multiple stages of rotary blades. The expanding gases cause the blades to rotate to power an upstream machine such as a generator to produce electricity, or otherwise generate a work load. A turbine stage may include a row of stationary vanes followed by a row of rotating turbine blades, where the turbine blades extract energy from the hot combustion gas for powering the compressor and providing output power as described. The stationary turbine vanes control the gas flow between successive turbine blades. In particular, the turbine vanes having intricately designed airfoil profiles to redirect gas flow exiting turbine blades, while minimizing temperature and pressure loss of the expanding gas.
One of the primary demands of turbine machine is maximizing the efficiency of the turbine operation. That is, generating more power or energy using less fuel. Various components of a turbine, for example vanes and blades, are constantly upgraded or modified to meet these demands. These turbine vanes and turbine blades are being constantly redesigned to meet the demands associated with the technological advances of turbines. More specifically, the airfoil profile of vanes and blades may be reconfigured to enhance the efficiency of turbine operations. By way of example, existing turbine machines that have been in operation over a number of years, and in some instance for decades, are often upgraded, which may result in the turbine vanes or blades airfoil profiles shifting away from an optimum aerodynamic design point. Accordingly, a need exists for an improved airfoil profile of a turbine vane, and especially a second stage turbine vane airfoil profile, to improve the aerodynamic efficiency of a turbine section of a turbine machine.